Burglar alarm



Sept. 29, 1925.

` A 1,555,563 s. FISCHER BURGLAR ALARM Filed Aug. v', 1922 s sheets-sheet' s Ll "l,

ff @ffy Patented Sept. 29, 1925.

UNITED STATES SIGISMUND FISCHER,

OF NEW YORK, N. Y.

BURGLAR ALARM.

Application filed August 7, 1922.

To all whom t may concern:

Be it known that I, SieisMUNn FISCHER, a citizen of the United States, and a resident of New York city, county and State ot New York, 'have invented a certain new and useful Improvement in Burglar Alarms, of which the following-is a specification.

This invention relates to burglar alarms and has for its primary object to provide electrically cont-rolled means included in either a normally closed or open circuit for operating audible and visual alarm devices, and means for automatically stopping the operation of the audible alarm device and resetting the control mechanism.

In one embodiment of the invention I provide an electric bell or other audible alarm device, an electromagnet and a vibrating armature interposed in the circuit thereor and means for closing` said circuit including` a lever, and resetting means for said lever actuated by the vibratory armature to return said lever to its normal position and open the operating circuit for the alarm device.

It is another object of the invention to novide means whereby the circuit of the lamp or visual signal is automatically closed simultaneously with the circuit for the audible alarm, said means however, maintaining the lamp circuit closed after the bell circuit has been opened.

It is a further general object of the invention to provide a burglar alarm as above characterized which is relatively simple in its construction, positive and reliable in its operation and which may be manufactured at relatively small cost.

lith the above and other objects in view, the invention consists in the improved form, construction and relative arrangement of the several parts as will be hereinafter more `t'ully described, illustrated in the accompanying drawings and subsequently incorporated in the subjoined claims.

In the drawings wherein I have illustrated one practical and satisfactory em bodiment of the invention and in which similar reference characters designate corresponding parts throughout the several views:

Figure 1 is an elevation, the cover plate or housing being removed and showing the several. 'operating parts in normal position; y Figure 2 is a fragmentary view similar to Figure l showing the relative positions ot the several elements `after the operating Cir- Serial No. 579,979.

cuits for the alarm devices have been closed ;v

Figure 3 is a detail elevation with certain parts broken away and others in section, illustrating the automatic resetting mechanism;

Figure l is an end elevation, the housing tive positions of the parts just after the` operating circuits for the alarm devices have been closed;

Figure 7 is a similar view showing the positions of the parts just before the circuit for the alarm bell is broken; and

Figure 8 is a diagrammatic view illus` trating the several control circuits.

In the accompanying drawings I have shown the several operating parts of the mechanism suitably mounted and supported upon a plate 5 to which the marginal walls of a suitable housing or casing 6 are adapted to be secured whereby the operating mechanism may be enclosed and protected.

For purposes of illustration, I have shown the audible alarm device in the form of an electric bell 7 which is connected -to one pole of the battery 8 by a wire 9 and to a post 10 by the wire l1, said post being mounted in the plate 5 and suitably insulated therefrom. It will, of course, be understood that the bell 7 can be arranged at any convenient location remote from the control mechanism therefor, on the exterior of a building. The other terminal of the battery 8 is connected by a wire 12 with a pivoted switch lever 13 also mounted on the plate 5 and insulated therefrom.

A pair of electro-magnets 14 are supported on the plate 5, one end ot an armature 15 being opposed to the magnet poles. This armature is yieldingly suspended from the post 10 by means ot a resilient strip 16 to which the armature is fixed at an intermediate point, one end of the said resilient strip being secured to the post 10 and the other end portion thereof being offset and bearing at its extremity against an adjustable screw 17 mounted in a stud 1S which is insulated from the plate 5. One side of the magnet hield is connected to the stud 18 by the wire 19 and the other side of said field is connected by the wire 2O with a contact plate 2l which is iiXed at one of its ends uponga stud 22 insulated from the .plate 5.

The pivoted lever 13 carries a pin 23 adapted to engage said contact plate when the arm is moved in one direction as will be later described.

A second pair ofy electro-magnets 24 are mounted on the plate 5, said magnets being supplied from battery 25 to which one side of the magnet field is connected by the wire 2G. The opposite pole of the battery is connected to the other side of the magnet field by the wire 27, there being interposed in this portion of the circuit a movable ele-ment 28 such as a door. lVhile the door remains closed, the circuit is closed and the electromagnets are energized. However, if desired, these magnets may be arranged in a nornally open circuit.

The armature 29 which is opposed at its 'upper end to the poles of the magnets 24 is pivotally supported intermediate of its ends upon a post 30 fixed in the plate 5, the lower end of said armature having a lug 31 extending angularly in one direction therefrom and being engaged by the free end of a leaf spring 30. This spring acts in opposition to the attractive forces of the magnets 24.

A plate 32 is suitably mounted upon the plate o in spaced parallel relation thereto. This plate is provided with a slot 33 in which a pin 34 fixed in the upper end of a pivoted lever 35 is engaged. The end of said pin is in contact with the obliquely inclined end edge 38 of the switch lever The lower edge of said arm at the inner end of the inclined edge 38 thereof is provided with a notch or seat 37 to receive the pin when the latter is positioned in the inner end of the slot 33. The lug 31 on the lower end of the armature 29 is held in bearing contact against the lever 35 bythe spring 30'.

In addition to the audible alarm bell 7, I provide a visual alarm in the form of a lamp 38 which is connected in a separate circuit. An arm 39 pivotally mounted upon the plate 5 and insulated therefrom is connected by the wire 40 to one side of said circuit, the other side of the circuit being connected through the lamp 38 by the wire 40 with the lower end of the pivotally mounted arm 41 mounted upon and insulated from the plate The free end of the arm 39 carries an insulation piece 42 which is maintained in contact with the upper edge of the switch lever 13 by gravity movement of the arm 39. The free end of this arm is likewise provided with a rectangular lug 43 on one side and an insulation piece 44 on the upper end of the arm 41 normally conn tacts with this lug. Thus the arm 39 is effectively insulated in the normal position of the parts from the arm 41 and the arm 13. A leaf spring 45 yieldingly urges the upper end of the arm 41 towards the lug 43.

Above the insulation 44 said upper end of the lever is recessed as at 46 to receive said lug.

As thus far described, the operation of the mechanism will be readily understood. Thus while the circuit for the electro-magnets 24 remains closed, the armature 29 is held in the position seen in Fig. 1 with the pin 34 in the outer end of the slot 33 and the pin 23 on lever 13 out of engagement with the contact 21. lVlien, however, said circuit is broken as by opening the door 28 and the magnets are deenergized, the spring 30 acts against the lower end of the armature 29, forcing the same inwardly. The pin 34 thus exerts a camming action against the inclined end 38 on lever 13 and forces said arm upwardly so as to bring the pin 23 thereon into engagement with the contact plate 21. Thus the circuit of the bell 7 is closed from one side of the battery 8 through wire 11, the armature 15 and electro-magnets 14 through wire 20, contact plate 21., lever 13, wire 12, back to the opposite side of the battery. Simultaneously, the arm 39 is lifted so as to position the insulation piece 44 on arm 41 below the lug 43 and permit the spring 45 to act and force the upper extremity of the lever into contactagainst one side of the lug 43. Thus the circuit of the lamp 38 is closed from the source of current through wire 40, arm 39, arm 41, lamp 38, back to the source of current.

The ringing of the alarm bell 7 is automatically stopped and the switch control lever 35 reset by means of the mechanism which I shall now describe.

A shaft 47 is journaled at its ends in the spaced plates and 32. Upon this shaft a ratchet disc 48 is fixed and at one side of said ratchet a worm 49 is secured upon the shaft.

An adjustable weight 50 is engaged upon the lower end of the armature 15, said weight acting as a pendulum in opposition to the attractive force of the magnet poles, such movement of the armature away from said poles being resisted by the spring element 16. A detent 51 is mounted upon the armature 15 intermediate of its ends and suitably insulated therefrom, said detent engaging the teeth of the ratchet disc 48. When the armature is attracted by the magnets 14, the detent rotates said ratchet disc and consequently the shaft 47, in one direction. Movement of the shaft in the opposite direction is prevented by a spring pawl 52 engaging the teeth of the ratchet disc.

An obliquely inclined shaft 53 is journaled at its ends in spaced bearings 54 on the plate 5 and has a worin gear fixed thereon meshing with the worin 49. A worm 56 is also lixed on said shaft and is engaged with the teeth of the worm gear ure 6.

57 secured upon a second shaft 58 mounted between the spaced plates 5 and 32'. In spaced relation to said worm gear a disc 59 is fixed on 4the shaft 5S and is provided in its edge with a notch or recess 60 which receives the lug 31 on the end of the armature 29 as said arm moves the switch operating lever inwardly, as above explained. Upon one sidey of the disc 59 a plate Gl is loosely mounted on the shaft 58. At one of its longitudinal edges this plate is formed with a lug or extension 62 projectingv beyond the periphery of the disc 59. A second plate 63 is also loosely mounted on the shaft 58 at the opposite side of the disc 59 and at its free end is` provided with the cam edge 641i. A pin 65 is fixed in the disc 59 and projects beyond the opposite faces thereof for engagement with the plates 6l and 63.

It will be apparentfrom the above description that as the armature 15 swings alternatelyr towards and away from the poles of the magnets lll, the shaft 47 is intermittently rotated and through the worm gearing, rotation is imparted to the disc 59 in the direction indicated by the arrow in Fig- In the rotation of said disc, the pin 65 carries the plates 6l and 63 upwardly until they reach a point beyond the center of gravity. The plate 6l will then drop downwardly until the lug or extension 62 thereof rests upon the lug 31 of the armature 29 while the plate 63 drops downwardly until its cam edge 6l strikes upon the pin 3l of the switch control lever 35.

It will be noted from reference to Fig. 7 that in the continued movement of the disc 59, the pin 65. again strikes the upper edge of the plate 63,. forcing the same downwardly so that its cam edge 64 urges the pin 23d outwardly in the slot thereby returning the lever to its normal position against the actionof spring and y,ino-ving the lug 3.1 of the armature 30 beyond the periphery of the disc. lVhen the plate is finally forced by pin 65 below the pin Sil and the end of the lever 35 is moved outwardly, the end of the plates 61 and 63. drop, downwardly and the plates are supported by a stop pin G6 fixed in the disc 59 and, jnojecting from the opposite sides thereof. However, if desired, this pin may be eliminated as it obviously is not essential. The circuit for the alarm bell is thus broken so that the bell stops ringing. However, the circuit for the lamp 38 is still closed and the lamp will remain illumined until the arm ll is manually returned to its normal position. For this purpose apin 67 may be provided fixed at one of its ends in said lever and projecting through a slot in the wall of the casing or housing 6. lVhen the circuit for the electromagnets Q-l is again closed, the lug 3l on the lower end of the armature 29 moves from beneath the lug or extension 62 of the plate 6l so that this plate will also drop downwardly by gravity and rest upon the pin 66.

In the drawings I have illustrated a manu ally operable stop member 68 in the form of a cylindrical rod, projecting outwardly through the wall of the housing 6 and provided with a suitable hand piece. 'I his rod is cut away or recessed on one side as at 69, said side of the rod being opposed to the switch control lever 35 in the operation of the mechanism. lVhen, however, it is desired for various reasons to make repairs, by simply giving the rod 69 a quarter rotation,y its convex side may be engaged with the edge of the lever so as to prevent the effective operation thereof.

From the foregoing description considered in connection with the accompanying drawings, the construction and manner of operation of my improved burglar alarm will be clearly understood. It will be seen that I have devised a very simple, positively operating and e'ticient mechanism for controlling the operation of audible and visual alarm devices and which may be adjusted so as to permit the audible alarm to operate for a predetermined length of time before such operation is automatically stopped and the mechanism reset. Obviously by properly adjusting the pendulum weight 50 the frequency of vibration of the armaturev l5 can be varied so as.` to correspondingly increase or decrease the extent of the interrupted rotary movements of the shaft 47. It will further be` seen that the several parts of the mechanism are very coinpactly arranged so that the entire device may be contained in a very small casing or housing and conveniently arranged in a wall, cabinet or safe where it will be inconspicuous.

While I have herein shown and described a preferred construction and arrangement of the several elementsl` it is nevertheless to be understood that the device mi ght also be produced in various other alternative construc-tions. Accordingly, I reserve the privilegeo'f resorting to all such legitimate changes in the form, proportion and arrange-ment ofthe several ele-ments as may be fairly considered within the spirit and scope ofthe invention as claimed.

I claim:

l. In combination with an electrical circuit, a switch interposed in said circuit, a second circuit including electro-mechanical means to actuate the switch in said first circuit to circuit-closing position, said means including a switch actuating member, resetting mechanism to move said member and automatically open said switch when said circuit has been closed for a predetermined length of time, means interposed in said first circuit and operatively influenced thereby for actuating said re-setting mechanism, a

lill

third circuit including a switch adapted to be closed by the operation ot' said actuating member in closing the switch in said first circuit, mean-s for maintaining the switch in the third circuit closed, and means for opening said switch.

2. In combination with an electrical circuit, a switch interposed in said circuit, electro-mechanical means independent of the circuit to actuate the switch to circuit-clos- .ing position, said means including a switch actuating member, re--setting mechanism to move said member and automatically open said switch when said circuit has been closed for a predetermined length of time, said resetting mechanism, and means interposed in said circuit including an adjustable pendulum for regulating the length of time said switch is to remain closed operated by the current in said circuit for actuating said resetting mechanism.

3. In combination with an electrical circuit, a switch 'for closing said circuit, iiicludiiig a movable part, a relatively movable actuating member limiting the movement of said part in one direction, electro-n'iechanical means independent of said circuit and controlling the movement of said member, said member when moved in one direction actuating the movable switch part to close the circuit, a` re-setting mechanism ifor said 'membeig and means interposed in said circuit and rendered effective upon the closing of the circuit to actuate said re-setting mechanism and move said member in an opposite direction to permit the switch part to return to its open position after said ciicuit has been closed for aA predetermined period of time.

4i. In combination with an electrical circuit, a circuit-closing switch including a movable switch part, a pivoted actuating member, electrical means independent oi said circuit ior moving' said member in one direction, mechanical means moving said member in the opposite direction when the electrical means is cle-energized, said member when moved in one direction co-acting with the switch part to move the Asame to circuit-closiiig position, mechanism for resetting said member independently o'f said electrical and mechanical operating means therefor to permit movement of the switch part to its open position, and means interposed in said circuit and operatively infiuenced thereby for actuating said re-setting mechanism.

5. In combination with two separate elecl trical circuits, a switch interposed in each circuit, the switch in one circuit including a pivoted part, an actuating member therefor normally positioned to limit movement of said switch part to its open position and operable to move said switch part to circuit-closing position, the switch in the other circuit including two pivoted members, one of said members being moved by the pivoted switch part in the first named circuit and insulated therefrom, insulation means carried by one of said pivoted members to prevent circuit closiiig contact of said members with each other, said member-s having parts for coacting engagement with each other to close the second named circuit when the hrst named circuit is closed, means for maintaining said second nained circuit closed after the pivoted switch part in the first named circuit returns to its open position, and means for returning the pivoted meinbers ot' the second named circuit to open position.

(i. A switch operating mechanism including in combination a fixed switch member, a movable switch member, means for moving said movable switch member into electrical contact with said fixed member including a pivoted lever adapted to be rocked to move` the switch member, a rotary cam adapted to be operated to return said lever so as to open said switch, a ratchet wheel operatively connected with said cam, an electromagnet, a vibrating armature for said electroinagiiet, a pawl carried by said armature for actuating said atchet wheel and cam, and a pendulum connected with said armature 'for regulating t-he period thereof, and the time required 'for opening said switch.

ln testimony that I claim the foregoing as my invention, I have signed my name hereunder.

SIGISMUN D FISCHER. 

